(text highlighted in pink was revised 101220)

Dr. Rancourt

Thank you for your interest in our publication, and the effort you have made to formulate the questions as they appear in

http://climateguy.blogspot.com/2010/11/peer-review-of-harrit-et-al-on-911-cant.html

Our answers follow below. Your questions are highlighted in green.

Yours sincerely

Niels Harrit

QUESTION: The Al slugs would give inhomogeneous background Al signals in the EDXA spectra. This was not considered or discussed in the paper. There could be no or little Al in the red-layer.

ANSWER:

When doing a scientific, instrumental investigation, there always is a great number of control experiments, which are implicit to every serious worker in the field. It is understood by the experienced reader, that these tests have been done, since you cannot put every basic control test image or report every bit of supporting data in a journal article. The articles would be so enormous that no one would bother reading them and no journal would possibly care to print them. There are some things that are implied.

Thus, numerous background studies were carried out which were not reported in the red/grey chips paper. Among them, we performed a background study where the SEM beam hit the pedestal directly. We found that the pedestal was not pure aluminum (as you somehow(?) anticipate), but rather an Al-Mg alloy.

Therefore, if we were picking up aluminum signal from the pedestal then we also would have seen Mg. We did not.

As the controls also showed, the electron beam couldn’t even penetrate the carbon conductive tab used as substratum for the chip samples during measurement. That is, the Al/Mg scaffold was never hit in any of the spectral recordings published in the article.

These circumstances are illustrated by Figs. 6 and 7 in the article. Fig. 6 shows the EDS spectra of the grey layers of four chips from each of the four dust samples. Thus, these data served as kind-of internal standard for the emissions obtained from the corresponding red layers (Fig. 7). In principle, the target areas for the electron beam on the two phases could be in a distance of microns only. It is immediately seen, that there is

1) No aluminum in the grey layer (and only traces of carbon – no magnesium), and

2) Plenty aluminium in the red layer (and plenty of carbon – no magnesium).

Taken together, Figs. 6 and 7 prove unambiguously, that the aluminum signal is specific for the red layer. That is, there is NO background contribution!

TEM wide-field studies aimed at determination of stoichiometric compositions of the red and the grey layers were carried out after publication article (and therefore should not go into this discussion). However, the samples were mounted on a copper holder and these measurements also confirm the presence of aluminum in the red material (in the platelets). If money and time permit, the TEM studies may be completed and published.

The spread of the electron beam inside the samples was tested and Monte Carlo simulations were performed to get an idea of the interaction volume of the electron beam within the sample.

To suggest that there is no aluminum in the red layer is ludicrous.

• QUESTION: The carbon adhesive tape will give inhomogeneous background C signals in the EDXA spectra. This was not considered or discussed in the paper. There could be no or little C in the red-layer.

ANSWER: Referring to the previous answer, it stands to reason that we acquired control spectra of the carbon tape on the Al stub, as well as on samples NOT mounted to carbon tape.

Again, comparison of figs. 6 and 7 reveals that the carbon signal almost exclusively originates from the red layer.

2

True, there seems to be carbon everywhere, which is exactly why some spectra were acquired from samples that were NOT mounted to carbon tape to ensure that the C was from the sample and not spurious X-rays from the carbon tape. In fact, one sample was mounted so that the X-ray signal could only possibly originate from within the red layer, and the measurement verified that there is carbon in the red layer.

The amount of carbon in the red layer had not been accurately determined at the time of writing and therefore we only reported qualitatively the presence of the C in the red layer.

Independently, the observation that the red layer swells in methyl ethyl ketone is an unambiguous proof that an organic matrix is present in the red layer only!

QUESTION: There is as much or more Si (silicon) in the EDXA results than Al in all the red-layer results and Si and Al are closely correlated in their spatial distributions (e.g., their Figure 10). No probable explanation is given for this. This is not consistent with the presence of metallic Al.

• ANSWER: Fig. 10 shows the elemental mapping BEFORE soaking the chip in methyl ethyl ketone. Please, compare with Fig. 15.

• QUESTION: Oxygen (O) is more closely spatially correlated with Al and Si than with Fe (e.g., their Figure 10). No probable explanation is given for this. This contradicts the conclusion of the presence of metallic Al.

• ANSWER: Fig. 10 shows the elemental mapping BEFORE soaking the chip in methyl ethyl ketone. Please, compare with Fig. 15.

• QUESTION: No effort was made to estimate the Fe:Al elemental ratio in the red-layer. Synthetic thermite or nanothermite would have a ratio of 1:1. The point is never discussed.

ANSWER: This ratio is not decisive. According to stoichiometry it should be 1:1. However, in real life there is always more aluminum. One reason is, that every aluminum item exposed to the atmosphere is covered by aluminum oxide. The relative fraction of Al2O3 increases as particles get smaller as a simple mathematical consequence.

Wonder where Dr. Rancourt got this information on nanothermite? Please provide a reference next time.

3

And what on earth is “synthetic thermite”?

In contrast, from the recipe provided in ref. 25 in our paper, one can derive an Fe/Al ratio of 0.17. But be sure that Lawrence Livermore National Laboratory would never publish a preparation of “the real stuff”.

QUESTION: The exothermic peak in the DSC traces occurs at a temperature (420 C) approximately 90 C below the temperature for the thermite reaction. No explanation is proposed for this. Chemical activation energies of known reactions cannot be so sample dependent, whether nano-sized or not. This is not the thermite reaction.

ANSWER: We do not claim that the red/grey chips are the same material as Tillotson et al. described. Actually, we are pretty sure it is NOT for the same - for reasons given above.

Your statement about activation energies is nonsense. An activation energy is a thermodynamic quantity referring to standard conditions in solution or in the gas phase. That some people take this lightly is another matter. But to postulate a unique correlation between ignition temperature and activation energy in a two-phase solid reaction is ridiculous. Well, maybe you can expect a lower ignition temperature the smaller the particles – as observed.

Of course, all samples have a different ignition temperature (Fig. 19), and of course, different preparations with different compositions will have different ignition temperatures.

And what do you mean by “the temperature for the thermite reaction”? You are going to have a very hard time if you try to search the literature for a well-defined ignition temperature of conventional thermite mixtures. Please, provide a reference next time you come up with such a statement.

Furthermore, in the paper we hypothesize that the organic matrix (plus atmospheric oxygen) is decisive for the low ignition temperature and the overall energy output.

• QUESTION: In the reacted product (after heating in DSC), no Al-oxide is observed as a residue, as required by the thermite reaction. No explanation is given for this.

ANSWER: Obviously, you have never done the experiment. In a conventional thermite reaction, you can observe the aluminum oxide as a white dust cloud (plume) leaving the reaction site. And if you care to watch the videos of the collapse

4

of the WTC towers, you may also observe, that the rocket-projectile fragments, which were ejected up-and-out from the towers, drew white smoke-trails after them. Gypsum from wallboard CANNOT account for this. Take a look!

• QUESTION: The obvious needed measurement of X-ray diffraction was not used to confirm the solid mineral species (oxides or metals). This is unacceptable in a materials chemistry paper. This is not considered by the authors.

ANSWER: X-ray diffraction studies on samples as small as these are very far from being a trivial matter. We did not have access to specialized X-ray sources (like synchrotrons) for this study.

• ALTERNATIVE HYPOTHESIS: Much is made of the fact that Fe-rich spheroids are present after reaction but there is no discussion of the grey-layer or of the origin of the Si-rich spheroids. Heating causes many things and there is an exothermic reaction so the conclusions about the presence of Fe-rich spheroids (which are reported to contain oxygen) as evidence for the thermite reaction is tenuous.

ANSWER: A scientific paper is a set of data and the best hypothesis rationalizing the observations. Fe-rich spheroids are observed after a thermite reaction. Fe-rich spheroids have never been observed unless there was a thermite reaction.

“Tenuous”?

ALTERNATIVE HYPOTHESIS: Here is an alternative explanation for the observations reported by Harrit et al.

Steel rusts. Rust crusts crack and blow off the steel when physically disrupted.

Rusting steel is one of the most studied materials science problems in engineering.

When steel rusts in a humid building environment it grows a crust composed of layers of different Fe-oxides and Fe-oxyhydroxides. These are stratified micro-layers with successive layers of different Fe-oxides species (wustite, maghemite, hematite, etc.). In a humid atmosphere the outer layers will be Fe-oxyhydroxides such as goethite, lepidocrocite and akaganeite. The latter three Fe-oxyhydroxides have the same chemical formula: FeOOH, and differ only in their crystal structures.

5

These Fe-oxyhydroxides typically form as nanoparticles and have the same needle and nanoflake-like morphologies as observed here.

When these Fe-oxyhydroxides are heated in a DSC they undergo a solid to solid exothermic reaction of dehydroxilation (loss of OH) and transform from FeOOH to Fe2O3 (hematite) at a temperature of approximately 400 C. The temperature of the transformation can vary depending on exact chemical composition, and on the crystal structure, but it is always at approximately 400 C.

Looks like our boys may have been discovering the properties of rusted steel. Steel contains C and Si which would end up in its oxidation products, especially in the oxyhydroxides.

ANSWER:

Sensational.

According to your suggestion, when you heat rust, elemental iron is formed.

I look forward to the publication of this hypothesis in – say - Journal of Inorganic Chemistry (an ACS publication). If supported by observation(!) - be sure it will be accepted promptly and be widely recognized.

Next time you present this hypothesis, the least you can do is to provide it with proper references and observations.

Yours sincerely

Niels Harrit

6